Tactile communication device and method

ABSTRACT

A device and method for use in tactile communications adaptable for use by anyone able to recognize messages written in a language known to them. The devise uses a series of sequentially firing vibromechanical stimulators vibrating against the skin or other suitably tactile sensitive area of the wearer. The vibromechanical stimulators are arrange in a substantially two dimensional array over the skin and are then triggered individually and in sequence, following a set of patterns representative of the symbols in the language recognizable to the wearer to tactually convey the message. The wearer cognitively perceives the tactual stimulation as a line or lines drawn on the skin or suitably tactile sensitive area that resemble the symbols used to communicate between the message sender and the wearer.

CROSS REFERENCES TO RELATED CO-PENDING APPLICATIONS

The present application is a continuation-in-part application of U.S.patent application Ser. No. 08/548,003 filed Oct. 25, 1995, titledTACTILE COMMUNICATION DEVICE AND METHOD and both applications are whollyowned by the inventor now U.S. Pat. No. 5,719,561.

FIELD OF THE INVENTION

The present invention relates to a communication device, in particular atactile communication device, as a personal communication device forreceiving messages and other useful information including navigationaland orientation information.

BACKGROUND OF THE INVENTION

Communication methods and devices have traditionally relied onaudiovisual modes to convey the message from a source to a recipient.Audiovisual modes are capable of conveying considerable amounts ofinformation within a reasonable time period with acceptable accuracy.The primary audiovisual modes of communication have relied on thereceiver's eyes and ears.

A lesser known and relatively uncommon mode of communication is tactilecommunication. As discussed below in more detail, efforts to developthis mode of communication have been limited and typically gearedtowards improving the communication reception for people disabled orimpaired in either hearing or vision. Tactile communications has notfound use in the general population essentially because of theoverwhelming reliance on audiovisual modes of communication.

Development of communication devices using the sense of touch in generalhave suffered because of a general lack of knowledge in the area ofunderstanding the sense of touch. There is also a relative lack ofsophistication of the sense of touch when compared with the acuity foundfor the senses of hearing and vision. By comparison, the sense of touchexhibits difficulty with localization and perception of a stimulus.Humans are able to see extremely fine patterns of surface asperity thatnonetheless feels as smooth as glass. The relatively low level ofsophistication of the sense of touch remains somewhat baffling in lightof the myriad types of end organ receptors that provide the brain withtactile information about our environment obtained through the sense oftouch.

Within the human body, tactile conditions are monitored through aninteraction of neuron end organ receptors within the skin and internalorgans and musculoskeletal system of the human body. Stimulation oftactile end organs sends a stimulus along the neuron of that end organto the sensory cortex of the human relaying the information typicallycarried by these nerves. There are a number of different types of endorgan effectors within a human. The general areas of sensory modalitydetected by skin receptors fall in the categories of fine or lighttouch, coarse touch, vibratory, pressure, pain, heat, and cold.Mechanoreceptor end organs are present within the human body in muscles,tendons and joints and provide important information concerningmusculoskeletal positioning and movement. Consequently, the sense oftouch can be distinguished by dividing into two general categories, thefirst being the exteroceptive sensory modality and the second categoryis the proprioceptive sensory modality. The general subject of thispresent invention will be concerned primarily with the exteroceptivetactile sensory modality.

The neuron end organ effectors in the exteroceptive modality are adiverse assortment of organelles. There are free nerve endings, Merkel'sdiscs, Meissner's corpuscles, Pacinian corpuscles, and Ruffini's endingssupplying tactile sensation to the skin. Free nerve endings predominateand are found generally throughout the entire skin surface area. Freenerve endings typically innervate the layers of the skin as unmyelinatedfibers carrying primarily pain as well as hot, cold and light touch.Free nerve endings with medium myelinated fibers are associated withhair follicles within the skin and predominantly supply light touchsensations.

Meissner's corpuscles are predominantly associated with the thicker skinof the palms and fingertips of a hand and the sole and toe tips of thefeet and primarily provide the perception of light touch in these areas.The high density of Meissner's corpuscles in the hands and feet is theunderlying anatomic basis behind the relatively exquisitely sensitivetactile abilities associated with the hands and feet and two pointdiscrimination. In contrast, Meissner's corpuscles are rare elsewhere inthe thinner skin of the human body. Contrast the decrease in Meissner'scorpuscles with a relative increase in the number of hair follicles andassociated free nerve ending fibers that provide the light touch sensorymodality to those areas of skin not associated with the palms or solesof the body. Consequently, the differences in light touch between thepalms, soles and the skin of the rest of the body lies not only in thedifference in neuron end organ effectors but also in whether the nervefiber is myelinated or non-myelinated. Merkel's corpuscles predominantlygive rise to vibratory sensing ability. As a consequence, Merkel'scorpuscles have less sensitivity to location and two pointdiscrimination but exquisitely sensitive to spatial resolution ofcomplex surface patterns when the fingers are scanned over an object orthe object moved over the fingers.

The quality of sensory ability is dependent on the ability of an endorgan effector (or free nerve ending) to sense the presence of astimulus, respond to that stimulus by propagating a signal along thelength of the neuron, recharge the neuron after its firing, and regainsensitivity to a stimulus following reception of the previous stimulus.These general areas of qualification of nerve function are threshold,conduction velocity, refraction, and adaptation. Non-myelinated fibersare generally slower to conduct, have higher periods of refractorinessand quickly adapt to external stimuli relative to myelinated fibers andthe converse is true wherein the greater the degree of myelination thehigher the conduction velocity, the shorter the period of refractorinessand the less susceptible to adaptation the nerve becomes. Additionally,the more sophisticated neuron end organs such as Pacinian corpuscle,Merkel's corpuscle, Meissner's corpuscle, and Ruffini's corpusclegenerally share a higher degree of sophistication as to structure andare associated with medium myelinated fibers. Contrast this with heavilymyelinated fibers used in the proprioceptive sensory modality whereposition sense, muscle force contraction and joint position arerelatively refined and sophisticated allowing us to perform fairlycomplex fine motor athletic movement. The heavily myelinated fibershaving the highest rate of conduction, the shortest period ofrefractoriness and the greatest resistance to adaptability.

Threshold of a nerve fiber will depend in great part to the type ofneuron end organ effector present on that nerve fiber. The threshold offiring will also depend on the type of stimulus being presented to theneuron end organ. Free nerve endings along the basement membrane of thecutaneous layer of the skin have little, if any, end organ structure tothem and have fairly low thresholds for firing. Free nerve endings arealso found to be fairly diffuse with the free end organs branching anumber of times and innervating a substantial area of skin in proportionto the size of the nerve fiber supplying that area. Consequently, thequality of signal received from free nerve endings has a generallydiffuse character poorly localized when compared to light touch providedby a Meissner corpuscle. A Meissner corpuscle is arranged in a tieredfashion of epithelial cells within the corpuscle with the main axis ofthe corpuscle perpendicular to the surface of the skin. This tieredarrangement, much like a stack of pancakes where each pancake representsa specialized epithelial cell and a nerve ending between the pancakes,is oriented in such a way as to be very sensitive to slight pressuresapplied along its major axis and relatively insensitive to pressuresarriving from a lateral direction. This directionality of a Meissnercorpuscle contributes to its greater ability to finally localize anddiscriminate from two different points accurately. Contrast a Meissnercorpuscle with a Pacinian corpuscle which essentially is a laminatedbody surrounding a single nerve ending. This lamellar construction withthe nerve ending at its center provides increased sensibility topressure from all directions but because of a lack of orientation thereis less sensitivity to discriminate size and location of the pressurestimulus.

Conduction velocity is a measure of the speed with which a nerve willtransmit to the sensory cortex of the brain the fact that a stimulus hasarrived at the nerve end organ. Myelination provides for higherconduction velocities where more myelin is associated with fasterconduction velocities.

When a nerve threshold is reached, the nerve fires and conducts a signalstimulus along its length and must then recharge the nerve in order tobe ready to respond to the next stimulus. The length of time that thenerve is discharged is known as the refractory period. The refractoryperiod is a state of non-responsiveness on the part of the nerve in thatit cannot respond to a continuing external stimulus during this period.

Neuronal adaptation is that ability of the nerve to modify its level ofsensitivity to changes in the environment. In effect, the neuron becomesused to the external stimulus and reestablishes a new level of responseto stimuli.

Tactile communication not only relies on the ability to sense that atouch has in fact occurred but also determine the nature of the touch.The touch should convey useful information. An example might be placinga car key in the hands of a blindfolded subject. The subject should beable to tell you not only that their hand has in fact been touched butbe able to discern from the pattern of the stimulus that you have placeda car key in their hand. This level of perception is defined asstereognosis which is the appreciation of a form of an object by meansof touch. With the perception of a key, the subject is able to tactuallyfeel a continuous surface and edge. In light of the anatomy anddistribution of neuron end organs contributing to tactual perception,the spatial resolution is limited by the spacing of single nerve fibersin the immediately surrounding area adjacent to that single nerve fiberand its end organ. As in the case of the fingertip and the high densityof Meissner's corpuscles, the perception of a spatial form on the skinof the fingertip would depend on a neuronal image of the stimulusestablished by the density of the Meissner corpuscles. The greater thedensity, the greater the perceptual ability to perceive complexity andthe greater the spatial resolution. The effect of this density patternof neuron end organs becomes readily apparent when considering asubject's ability to discriminate between two points. Our tactileability to resolve a form spatially is enhanced if we then rub ourfingers over the object, such as the key. This scanning motion sets up avibratory sensation to which Merkel's corpuscles may respond. Thevibratory sensation builds up an image that is resolvable at dimensionsless than a millimeter.

In the article titled “The Perception of Two Points is not the SpatialResolution Threshold”, K. O. Johnson et al., in Touch, Temperature, Painand Health Diseases: Mechanisms and Assessments, Progress and PainResearch and Management, Vol. 3, edited by J. Boivie et al., the authorsdiscuss the tactual difference in perceiving a two point discriminationversus spatial pattern recognition thresholds. In their review, Johnsonet al. discuss the responses evoked by one and two point stimuli versusthe neural mechanisms associated with tactile spatial resolution. Theresults demonstrate that there is a distinctly different mechanism ofresponse by a human subject when presented with a single probe, a doubleprobe or a more complex vibratory pattern. Furthermore, they are able toshow that response to one and two point stimuli will produce differentsensations depending upon longitudinal or transverse orientations of theprobes which would allow discrimination between one and two pointsstimuli on the basis of cues that may have had nothing to do withspatial resolution. Furthermore, they were able to demonstrate that thethreshold of tactile spatial resolution has remained independent of thetwo point discrimination threshold. It has been shown that theneurologic system responsible for tactile spatial pattern recognition atthe limits of resolution is the slowly adapting type 1 (SAI) afferentfiber system. The individual SAI afferent fibers terminate in Merkelreceptors and have high spatial resolving capacity. Contrast this withrapidly adapting (RA) afferents which terminate in Meissner corpusclesand have poor spatial resolving properties. Meissner corpuscles haverelatively high density in the fingertips and palms of the hand and toesand sole of the feet. As noted above, this high density provides forsubstantially increased two point discrimination resolution, i.e., theability of a subject to determine whether they are being touched by asingle or two separate probes simultaneously. Contrast this with aplurality of probes that are in a spatially configured pattern, forinstance the letter “A”, such that if all of the probes come intocontact with the skin surface of a fingertip simultaneously, thequestion becomes will the subject be able to discern and resolve thespatial configuration of the multiple probes if the probes are spacedtogether less than the two point discrimination threshold or if theprobes are spaced apart greater than the two point discriminationthreshold.

To evaluate this question, consider a device known as the Optacondeveloped by Bliss and noted in the paper “Summary of Optacon RelatedCutaneous Experiment”. In the conference on cutaneous communicationsystems and devices, F. A. Geldard, editor of the Psychonomic Society,1974. The Optacon uses an array of 144 probes in a 12×12 pattern. Thearray measures approximately one to one and one-half centimeters on eachside. Consequently, the distance between one probe and its nearestpartner is approximately one millimeter. The Optacon takes visualrepresentation of a letter or number as its input and extends theappropriate number of probes from the surface of the array to spatiallycorrespond to the letter or number being visualized. For example, theletter “A” may use upwards of thirty probes simultaneously contactingthe skin of a subject's fingertip with each probe no greater thanapproximately one millimeter from its nearest neighbor. Therefore, ifthe two point discrimination threshold is two millimeters, all thirty ofthe protruding probes from the array will be indistinguishable from eachother and perceived as a single probe fairly broad in its size.

As demonstrated and discussed above, Meissner corpuscles arepredominantly responsible for two point discrimination. Merkel discs, bycontrast, are responsible for spatial resolution. However, to takeadvantage of Merkel's disc stimulation, the Optacon and similar devicessuch as U.S. Pat. No. 3,229,387 issued Jan. 18, 1966 to Linvill, use aplurality of probes in a fairly large array such as the 12×12 array ofthe Optacon. The array is used to scan across a page of letters andnumbers while attached to a fingertip surface and the letters andnumbers through protruding vibrating probes are then felt to scan acrossthe fingertip much as a ticker tape output scans across a marquee. Forexample, the Optacon slides across the letter “A” and the letter “A” isfelt to slide across the fingertip of the wearer of the Optacon.Sequential numbers of probes in the pattern “A” protrude from thesurface of the array and vibrate at a set frequency. Depending upon thesize of the letter there may be upwards of thirty or forty probessimultaneously vibrating against the surface of the subject's fingertip.It is the combination of the changing sequence of simultaneouslyvibrating probes and the vibration of the probes that contributes to thesubject perceptually identifying the spatial resolution of the letter.If the letter were to not scan but remain static with the thirty or soprobes arranged in a letter but vibrating against the subject'sfingertip, the subject would not resolve the pattern into any usefulrecognizable alphanumeric. And as noted above, it has been shown thatthe SAI fibers terminating in Merkel's discs contribute to the spatialresolution perceived by a subject using a device similar to the Optacon.

Tactile stimulators may be generally divided into two groups: Thesynthetic systems and the analogic systems. These systems are devices inwhich the cutaneous sensory system is intended to replace one of theother sensory systems, most commonly vision or hearing. Examples ofanalogic audio systems are cochlear implants that convert sounds such asspeech into tactile sensations felt by a subject at a site designed tobe used by the device. The ability to transmit speech to the skin usinga single vibrating transducer generally has failed in attempts.Continued work in this area has led to the development of systems whichelectrically divide the speech spectrum into different frequency bands.These various bands may also be modified in terms of time delay schemesand positioning to more closely accommodate the direction of the actualsound source.

Other audio tactile aids are known as vocoders. A number of vocoderdevices have been tested and an evaluation of two multichannel tactileaids can be found in the paper “Evaluation of Two Multichannel TactileAids for the Hearing Impaired”, Weisenberger et al. in the Journal ofAcoustical Society of America, Vol. 86 (5), pp. 1764-1775, November1989. The two vocoder devices described used 16 element linear vibratoryarrays displaying activity in 16 overlapping frequency channels. The 16elements vibrated simultaneously with the frequency ranges approximatelya third of an octave in bandwidth spaced evening over the frequencyrange between 140 to 6,350 Hz. Accuracy of communicating with thesevocoders was limited with subjects being able to identify only 70% of a250 word test list even when combined with lip-reading.

All of these analogic systems replacing hearing use multiplevibrotactile probes vibrating simultaneously at frequenciesapproximating those of actual speech. These systems have provendifficult to incorporate and accurately rely on.

Visual analogic systems are represented by such devices as the Optaconor a tactile vision information system (TVIS) as described in “EffectiveTactile Stimulation Pulse Characteristics on Sensation Threshold andPower Consumption”, Nuziata et al., Annals of Biomedical Engineering,Vol. 17, pp. 423-35, 1989. The authors describe the basic function ofthe TVIS as the acquisition of an optical image with a video camera andthe transformation of the image or some portion of the image into avibratory pattern on a specific region of skin. Like the Optacon, theTVIS uses a vibratory tactile array coupled with appropriate electronicfrequency filtering in order to create a spatial analog of the visualscene being picked up by the video camera. Each vibrator used a basefrequency of 250 Hz. The choice of 250 Hz was dependent on the minimumthreshold for tactile sensation using Pacinian corpuscles that are themost responsive end organ receptors in the vicinity of 250 Hzstimulation frequencies. Both the Optacon and the TVIS use multiplevibrating probes in a spatial pattern to create the vibrotactile messagediscerned by the subject using the device.

While an analogic system such as the Optacon, where the device usesmultiple simultaneous vibrotactile probes to create a complex spatialform, confusion and difficulty with perception has been studied. In thepaper “The Effects of Complexity on the Perception of VibrotactilePatterns”, Homer, Perception and Psychophysics, line 49 (6), pp. 51-62,1991, the author identified tactile confusion for letters with a greaternumber of lines such as the letters M, W, B and K. Therefore, despitethe spatial threshold being significantly less than the two pointdiscrimination threshold, the difference of 0.9 millimeters versusapproximately two millimeters for the overlaying skin of a fingertip,complexity of the spatial form remains an obstacle difficult toovercome.

Synthetic systems employ communicating with languages employingsynthetic codes. Braille is the most useful, best known and longestlived example of the synthetic families of tactile codes. Braille uses a2×3 array to form unique patterns discernible as the alphabet.Consequently, the tactile experience does not resemble either the visualor auditory experience associated with the letter for which the patternstands. In the simplest of terms, synthetic systems require that theuser of the system learn the additional language set employed by thesynthetic system.

Translation of Braille into a vibrotactile device would necessarilyrequire an array 2×3 and be capable of simultaneously vibrating up toall six of the probes. As with the Optacon, to achieve the smaller sizesand utilize the lower threshold associated with spatial resolution ofcomplex forms, the Braille patterns would necessarily need to be scannedacross the skin surface, preferably the tip of a finger. Consequently, adevice useful for tactually displaying Braille figures would need anarray having substantially greater than six vibromechanical probes.Without the scanning capability, a device incorporating Braille as theunderlying interpretive language would use a minimum of sixvibromechanical probes, each requiring spacing between probes to begreater than the two point discrimination threshold. This minimumspacing is necessary to allow the subject wearing the device to discernbetween two or more probes, since Braille characters require anywherefrom one to six simultaneously vibrating probes.

The communication systems described above have been developed as devicesto provide communication devices to subjects who are otherwise impairedwith either visual or auditory abilities to communicate. Whethersynthetic or analogic, these systems generally rely on Merkel's discsdensely populating the fingertips to achieve spatial resolutionthresholds low enough to communicate complex spatial forms such asletters and numbers.

There exist other tactile phenomena that are not well understood. Anexample of such a tactile phenomenon is described in the paper “ApparentHaptic Movement” by Sherrick, et al., in Perceptions and Psychophysics,Vol. 1, pp. 175-180, 1966, wherein the author describes the induction ofa sense of movement produced by stationary vibrators sequentially firedover the surface of the subject's body. The authors describe one examplewhere an intense sense of rotational motion was induced by successivelyfiring six vibrators placed around a subject's chest. The authorsfurther studied a subject's sensation of haptokinetic movement employinga device with two vibrators spaced at different distances, from 4 to 22centimeters, along the length of the subject's leg. The subject wasallowed to control the duration of the two vibrotactile bursts as wellas the interval of time between the onset of the two vibrotactilebursts. In this way, the subject was able to adjust the sequentialfiring of the two vibrators to achieve a maximum perception of hapticmovement between the two vibrators. For each trial run, the vibratorswere vibrated at 150 Hz for burst durations ranging from 25 to 400milliseconds (msec) which equates to from 4 to 60 vibrations per burst.The interval between burst onsets ranged from 75 to 400 msec.

A different tactile phenomenon was induced in subjects using a systemslightly different than the previously described system as outlined inthe journal article “The Cutaneous ‘Rabbit’: A Perceptual Illusion” byGeldard et al. in Science, Vol. 176, pp. 178-179, Oct. 13, 1972. Theseauthors used from two to five vibrators consisting of a short length oflucite rod about 0.6 centimeters in diameter with a rounded tip rigidlymounted on Clevite bimorph benders and driven by a pulse generatorgenerating a square wave pulse 2 msec in duration. Each vibratorreceived five pulses separated anywhere from 40 to 80 msec between eachpulse. The vibrators were aligned in a linear array over a subject'sforearm and upper arm on an average spacing of approximately tencentimeters with a range from two centimeters to 35 centimeters. Thephenomenon experienced by the subjects in the test was the sensation ofa smooth progression of jumps, or taps, on the arm between thesuccessively firing vibrators. It was described as if a tiny rabbit werehopping from one vibrator to the next. If the number of vibrator taps isincreased for each vibrator then the hops become shorter and closertogether and the opposite effect is also noted. The authorsdistinguished this rabbit effect from the vibrotactile movementdescribed above by Sherrick, et al., on the basis that the rabbit effectgives a discontinuous hopping sensation described as discreet tapsbetween the stimulus loci which is in contradistinction to thecontinuous vibrating gouging sensation in the skin between lociexperiencing the vibrotactile or haptokinetic movement illusion.

The devices that attempt to replace vision or hearing do so by relyingon a plurality of vibrators firing simultaneously to reproduce either acomplex spatial arrangement such as a letter or number or to recreatethe vibrations associated with speech. These systems consume aconsiderable amount of power to fire the plurality of vibrator arrayssimultaneously and are dependent on their interaction with Merkel'sdiscs, Meissner's corpuscles or Pacinian corpuscles to relay thecommunication information from the vibromechanical device to theconscious awareness of the recipient.

The perceptual phenomena described with the vibrotactile or haptokineticmovement and the rabbit affect appear to be independent of Meissner'scorpuscles, Merkel's discs or Pacinian corpuscles since thevibromechanical stimulators are placed independent of, and in fact canbe varied in their distance between each locus and still create theillusion of movement between the stimulator loci. These phenomena appearto be more a function of perception at the sensory cortex level as thestimuli are reconstructed in real time and perceived at a consciousawareness level by the subject. Therefore, these phenomena appear to beindependent of two point discrimination and spatial resolutionthresholds.

There does not as yet exist a vibromechanical tactile communicationdevice capable of universal use that can receive and convey informationto the wearer conveniently or accurately.

SUMMARY OF THE INVENTION

The present invention discloses a method and device for vibromechanicaltactile communications adaptable for use by anyone able to recognizealphanumeric messages in a language, in other symbols known to them, oreven in symbols or communications formats that are learned specificallyfor use with the present invention. The present invention uses a seriesof sequentially firing vibromechanical stimulators vibrating against asuitably tactile sensitive surface of the wearer, such as skin or buccalmucosa, to induce a phenomenon of illusion of linear continuity. Thisillusion of linear continuity, through vibromechanical stimulatorstapping on the suitably tactile sensitive surface of the wearer, can beused to produce simple or complex pattern configurations perceivedcognitively by the wearer of the device as line drawings or “tracings”,such as alphanumerics or other tactual patterns recognizable by thewearer, or perceived as an induction of motion.

Although the wearer is receiving discrete tappings on the surface area,the patterned vibratory stimuli are consciously perceived as theuninterrupted dragging of a blunt tipped stylet across the subject'stactile sensitive surface, i.e., a “tracing” across the surface. Theclosest somatosensory equivalent to this phenomenon is the tactile andcognitive sensation known as graphesthesia. In the present invention theplurality of vibromechanical stimulator are arrangeable in an array, oras a single line of multiple vibrators. Each vibromechanical stimulatorin a two dimensional array is spaced apart from its nearest neighbors adistance that is still within the two point discrimination thresholddistance for the suitably tactile sensitive surface area beingstimulated. The vibromechanical stimulators in a linear arrangement donot need to be constrained within the two point discrimination distance.Each vibromechanical stimulator is triggered to vibrate individually andsequentially from one stimulator to the next successive stimulator forthe pattern chosen to be conveyed.

One embodiment of the present invention is a tactile communicationsdevice (TCD) for use by a human wearing the device against a tactuallysensitive surface of the human and receiving and convertingcommunication elements of a data stream into a tactual messagehaptically or cognitively perceptible to the human. The device comprisesa housing including a power source and a tactile stimulator arraymountable within the housing. The array includes a plurality ofvibromechanical stimulators positionable in a substantially twodimensional array, the array being abuttably positionable over asuitable tactile sensitive surface area of the human and the pluralityof vibromechanical stimulators being connected to the power source. Acontrol circuit is connected to the power source and to the tactilestimulator array for independently and sequentially controlling eachvibromechanical stimulator. The control circuit preferably includes areceiver for receiving alphanumeric and/or other communication elementsof the data stream, a tactual pattern storage circuit for storing apatterned sequence of turning on and off at least one vibromechanicalstimulator of the plurality of vibromechanical stimulators correspondingto each tactual pattern stored, and a conversion circuit for convertingthe received communication elements of the data stream into a tactualdata stream according to the corresponding tactual pattern.

As a consequence, for each alphanumeric and/or communication elementwithin the data stream, beginning with the first datum, thecorresponding tactual pattern is used to turn on and off a sequence ofvibromechanical stimulators, one vibratory stimulator at a time,following the pattern sequence for each alphanumeric and/orcommunication element converted from the data stream.

The type of communication of information useful in a tactilecommunication device is limited only by a person's ability to perceivetactually. Virtually all forms of communications are transcribable tosome form of a tactual pattern that is either associated with apreviously learned symbol, such as alphanumerics, or is at leastlearnable, such as orienteering directions or navigational vectors. Thistype of communication may be stand alone or incorporated into otherdevices such as a watch, pager, or other devices that also traditionallycommunicate in audio or visual alphanumerics with the user. The use ofthe device of the present invention is not limited to humans.Realistically, the device of the present invention is useful forconveying any tactual message to any animal that has a tactuallysensitive surface. The list of such animals includes most mammals. Theanimal must be capable of learning the association of the symbol orcommunications element, or elements, received to the response desired ofthe animal. For the purposes of this disclosure, the terms wearer, userand human should not be construed so narrowly as to limit the scope ofthese terms to just humans, but should be read to include any animalhaving a tactually sensitive surface.

Information other than alphanumerics or symbol data is also conveyableby the present invention. Consider a tactile position localizationdevice (TPLD) housed in a suitable housing. By way of example, a pilot,deep sea diver, or even an astronaut, may wear a two dimensional arrayacross their chest, leg, back, or elsewhere, and tactually receivespatial orientation information from their navigational instrumentationthrough an appropriate interface. The type of message received andconveyed to the wearer of a tactile array for representing spatialorientation information may incorporate any type of message formatdesired, as long as the format is taught to the wearer. For instance,consider a pilot wearing an array across his or her abdomen wherein thearray “traces” a straight line across the pilot's abdomen sequentiallyusing one tactile stimulator at a time. Through training, the pilotknows that when the line is traveling from left to right at about thelevel of the pilot's umbilicus, the pilot knows that the plane is flyingupright and level with the horizon. Nose up or down, or turninginclinations would lead to corresponding changes in the line being“traced.” For nose up, the line would move above the pilot's umbilicus,and vice versa for nose down. During turns, the line would also bank inthe same direction, and to the same degree, as the wings are banked. Thepilot would even know when the plane is inverted, after having gonethrough half a roll, for the line is now moving right to left across thepilot's abdomen.

Another formatting example is the supplying of directional, ornavigational, information, such as information telling a pilot whichdirection to fly. A specific example is an airplane's instrument landingsystem (ILS), usually providing visual guidance to the pilot on landingapproaches. The tactile array could be programmed to receive data fromthe ILS and graphically represent that data tactually across the pilot'sskin in the form a horizontal line to indicate the airplane's relativeposition to the glide path, and a vertical line to represent theairplane's relative position to the runway centerline. The array would“trace” a horizontal line, to be followed by a vertical line, and thenrepeat the process as quickly or as slowly as desired, updating theinformation from the ILS instrumentation as often as needed. In thisfashion, the pilot may then fly the airplane to the lines being “traced”across their skin much as they would fly their airplane to the linesvisually displayed on their cockpit ILS instruments. The pilot couldfeasibly land the plane without using, or relying on, any other cockpitinstruments, or without visual cues through the cockpit windows.

Additional TCDs could be used with a TPLD to provide the pilot withadditional alpha-numeric information such as their heading, wind speed,altitude, and angle-of-attack. An alternative to multiple TCDs ismultiplexing data input into a large TPLD array, for example, an arrayhaving 100 or more individual stimulators in a rectangular or squaregrid placed across the pilot's chest and abdomen or back, wherein ILSglide slope and flight path could be given as horizontal and verticallines, respectively, and other information, such as spatial orientation,altitude, angle of attack, and air speed could be given in smaller areasof unused corners of the array, with all the data being updated as oftenas desired by the pilot.

Another embodiment of the present invention is a tactile egovectiondevice (TED) for use by a human wearing the device against the skin ofthe human. Egovection is a useful term for describing inducing a senseof motion in a person, where, in fact, the person is not moving at allrelative to their surroundings. Such a phenomenon may be encountered invarious pathological conditions, such as labyrinthitis, an inflammationof the semi-circular canals of the inner ear, that induce the sensationof spinning in a person. Egovection may also be artificially induced bytactually stimulating a persons body, circumferentially about a centralaxis, one vibromechanical stimulator at a time, according the presentinvention.

Such an embodiment comprises an array of a plurality of vibromechanicalstimulators suitable for arrangement circumferentially axially aroundthe person's head, neck, thorax, or abdomen. The axis may be in any oneor all three axes. The plurality of vibromechanical stimulators areelectrically connected to an electrical power source. A control circuitis electrically connected to the electrical power source and the tactilestimulator array for independently and sequentially controlling eachvibratory stimulator. The control circuit includes a program forsequentially firing the plurality of stimulators, one stimulator at atime, in either direction around the circumference of the person and atvariable rates of firing.

The present invention embodies a tactile communications method forreceiving and converting a communications data stream into a messagehaptically perceptible to a human. The method comprises the steps ofattaching a housing to the human with the housing including anelectrical power source, then mounting a tactile stimulator array withinthe attachment housing, the stimulator array having a plurality ofvibromechanical stimulators in a substantially two dimensional array.Next is positioning the tactile stimulator array abuttably over atactually sensitive surface area of the human, connecting the pluralityof vibromechanical stimulators electrically to the electrical powersource, storing a tactual pattern for each alphanumeric and othersymbol, controlling each vibratory stimulator independently andsequentially using the stored tactual pattern for each symbol, receivingelectronically an alphanumeric and/or other symbol data stream,converting the received data stream into an tactual pattern data streamaccording to the corresponding stored tactual patterns, and turning onand off a sequence of vibromechanical stimulators, one vibratorystimulator at a time, according to the corresponding tactual patterndata stream for each alphanumeric or other symbol datum within thetactual pattern data stream, beginning with the first alphanumeric orother symbol datum, such that the sequence of vibrating stimulators onthe tactually sensitive surface area is perceived tactually by the humanas the communications message. The present method also includes a stepfor controlling the sequence of vibratory stimulator on and off timesand intervibratory latency time periods. This method provides for aperson to cognitively experience the complete or whole alphanumeric, orother symbol, message through the illusion of linear continuityphenomenon.

It is an object of the present invention to provide a method and devicefor tactile communications useful for persons who are sighted and havehearing, as well as, for persons visually impaired and/or hearingimpaired. The device of the present invention is anticipated toaccurately convey a message to the wearer of the device even while thewearer is engaged in other activity, such as sporting activities,driving or flying.

It is an additional object of the present invention to provide a methodand device capable of accurate and timely tactile communications inmany, if not all, the known written languages as well as in complexsymbols and codes mutually known between the sender of the message andthe wearer of the device.

The above and other objects and advantages of the present invention willbecome more readily apparent when reference is made to the followingdescription, taken in conjunction with the accompanying drawings, andare in no way intended to limit the scope of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side elevational view of an embodiment of the presentinvention with the outer housing depicted in phantom for better clarity,the electronic components in block diagram and the array componentpartially sectioned for clarity;

FIG. 2 is a bottom plan view of the housing of the embodiment depictedin FIG. 1;

FIG. 3 is a cross-sectional view taken at the line 3—3 in FIG. 2;

FIG. 4 is a perspective view of the embodiment of FIG. 1 as anembodiment of the invention to be worn on a wearer's skin;

FIG. 5 is an additional perspective view of the embodiment of FIG. 1;

FIG. 6 is a bottom plan view of an additional embodiment of the presentinvention;

FIG. 7 is a bottom plan view of another additional embodiment of thepresent invention;

FIGS. 8(a) through 8(k) are representative examples of how an embodimentof the present invention functions to generate numeric tactilecommunications;

FIGS. 9(a) through 9(d) are representative examples of how anotherembodiment of the present invention functions to generatenon-alphanumeric tactile communications in addition to alphanumeric.

FIGS. 10(a) through 10(b) illustrate the placement of tactilestimulators on and around a wearer's chest and torso.

FIGS. 11(a) through 11(c) illustrate the placement of a tactilestimulator array on or around the head of a wearer.

FIGS. 12(a) through 12(c) show the placement of multiple stimulatorarrays around the head of the wearer.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 depicts an embodiment of the present invention as a tactilecommunication device 30 which includes a control module 32, a stimulatorarray 34, a power source 36, and a housing 38. Tactile communicationdevice 30 is an electromechanical device capable of receiving messagesfrom an internal source transmitted to tactile communication device 30from a remote device and then delivering the message to the user oftactile communication device 30 as a tactually sensed and cognitivelyperceived message.

Control module 32 includes a data receiver 40, a pattern memory module42 and a conversion module 44. Data receiver 40 comprises an electronicdata reception capability preferably as radio frequency electroniccommunications. As a receiver, data receiver 40 will receive messages inthe form of a data stream. The data stream itself may include analog,digital or combinations of these forms or other forms. Data receiver 40is electronically connected to pattern memory module 42 via a memorydata transfer bus 54. Data receiver 40 is also electronically connectedto conversion module 44 through a message data transfer bus 52. Patternmemory module 42 is electronically connected to conversion module 44through a memory data transfer bus 54. Data receiver 40 iselectronically connected to pattern memory module 42 through a memoryrewrite transfer bus 56.

Power source 36 delivers electrical energy through electrical connectors50. As depicted, power to stimulator array 34 is received through aplurality of electrical connections 48 between control module 32 andstimulator array 34.

Stimulator array 34 includes a plurality of vibromechanical stimulatorssuch as an array of electrical solenoids 46. Suitable alternativevibromechanical stimulators are available such as bimorph ceramics andpiezoelectric materials. Stimulator array 34 is constructed to present atwo dimensional array of vibromechanical stimulators across a housingface 58 having corresponding housing face apertures 60 through whicheach vibromechanical stimulator may protrude and retract a tactileeffector portion of each vibromechanical stimulator.

One embodiment of the two dimensional array of housing face apertures 60in housing face 58 is depicted in FIG. 2. There are depicted eighteenhousing face apertures 60 arranged in three columns of five and a singlecolumn of three housing face apertures 60.

FIG. 3 depicts an example of a vibromechanical stimulator with a tactileeffector portion as a solenoid 46 with its electrical connection 48 anda solenoid piston 62. As shown, solenoid piston 62 acting as a tactileeffector is in a retracted position and upon energizing solenoid 46,solenoid piston 62 will be forced out aperture 60 through housing face58.

Tactile communication device 30 is depicted in FIG. 4 using a band 64 toattach housing 38 to the skin of a wearer such as a forearm 66 much likewearing a watch. As depicted, the orientation is to place housing face58 against the surface of the wearer's skin. In this orientation, thevibromechanical stimulators will come into contact with the surface ofthe wearer's skin when the stimulators are energized. An example isdepicted in FIG. 5 where one of the solenoid pistons 62 projects throughits corresponding housing face aperture 60 and extends beyond theboundary of housing face 58 surface. As worn against a wearer's skin orother suitably tactile sensitive surface, projection of any of thesolenoid pistons 62 impinge against the wearer's skin and convey atactual stimulation to the wearer.

FIGS. 6 and 7 represent two additional embodiments of many possibleembodiments for number and the two dimensional positioning of housingface apertures. The present invention anticipates that many differenttwo dimensional arrays are available both in spatial orientation and intotal numbers of vibromechanical stimulators used. For example, asdepicted in FIG. 6, there are twenty-one housing face apertures withtwenty in a housing face aperture array 68 that is four columns of fiveapertures. There is an additional aperture 70 placed to the side ofaperture array 68 as an asymmetric configuration providing thisembodiment with an aperture array capable of employing the asymmetricaperture 70 within the complete array or alternatively using aperture 70and its corresponding vibromechanical stimulator to provide anasymmetric stimulus that may carry additional meaning. An example mightbe triggering the vibromechanical stimulator through aperture 70 toindicate that the tactile communication device is about to begin amessage transmission, or switch from alphabet to numeric or evenpossibly denote when the next character to be delivered is a knowncomplex pattern alerting the wearer to pay a heightened level ofattention to the next character so as to discern its true nature.Further use of an asymmetric aperture such as aperture 70 will bediscussed below.

FIG. 7 depicts an embodiment using twenty-one apertures in a housingface aperture array 72 having the shape of an hourglass in its twodimensional configuration. This particular arrangement depicted byaperture array 72 was arrived at through studies to determine the mostefficient two dimensional array pattern for being able to trace all theletters of the English alphabet and the complement of arabic numerals asdiscussed below. Depiction of these three aperture arrays in no wayshould be construed as a limitation in the actual number of useful twodimensional arrays available to the present invention. Although notdisclosed, additional two dimensional patterns have been studied anduseful arrays have been constructed from patterns employing as few asnine vibromechanical stimulators to as many as thirty. Arrays utilizingfrom fifteen to twenty-three vibromechanical stimulators havedemonstrated the greatest practicality in terms of highest efficiency atthe lowest cost and still providing accurate rendition of the receivedmessage.

FIGS. 8(a) through 8(k) depict the sequential firing of an array ofeighteen (18) vibromechanical stimulators using the array pattern shownin FIG. 8(a) to generate the numbers 0 through 9. This particular arrayis convenient for generating letters as well as numbers. FIGS. 8(b)through 8(k) depict which numbered stimulator firing sequence is used toproduce each of the numbers.

FIGS. 9(a) through 9(d) depict a large array 100 using a 14 by 21vibromechanical stimulator array totaling 294 stimulators beginning witha first stimulator 102 numbered as “1” on the array face and, forconvenience, each of the corner stimulators also bearing theirappropriate sequential number on the array face. Such a large array isuseful for tactually conveying non-alphanumeric information, such asspatial orientation and navigational headings information, as well asalphanumerics. This type of information is not standardized, as isalphanumeric information, and as a consequence the format for tactuallyconveying this information relies on choosing a format for presentationthen teaching that format to the user of the device. With this type ofopen ended formatting, many different and useful formats may be chosenand adapted for tactually conveying useful information to a wearer ofthe present invention. Examples of orientation and navigationalinformation are those data receivable from flight instrumentation,global positioning satellites, diving instruments and the like.

In operation, tactile communication device 30 is powered by an internalpower source 36 preferably a power source capable of deliveringintermittent high peak current suitable for energizing thevibromechanical stimulators chosen and additionally providing sustainedlow current power suitable for radio receivers and integrated circuitsboth digital and analogic.

Data receiver 40 comprises an appropriate radio receiver including anantenna for reception of a radio signal bearing the message to becommunicated to the wearer of the device. The message may be in the formof digital or analog data streams and data receiver 40 will be set upaccordingly. An additional mode of operation for data receiver 40 isreception of commands for both altering programs as well as the symbolpatterns that are stored in pattern memory module 42. The most commonpatterns stored will be those consisting of the alphabet from A to Z andthe set of arabic numerals. The symbol pattern is stored in patternmemory module 42 so that the appropriate symbol matching the symbol sentin the data stream to the data receiver 40 may be sent by pattern module42 over memory data transfer bus 54 to conversion module 44. The presentinvention anticipates that other symbol sets may be utilized by thepresent invention, for example, coded symbol sets where an encryptionand de-encryption scheme is shared between the source of the encodedmessage and the wearer of the device, the Cyrillic alphabet, the Greekalphabet and even, but not limited to, Chinese and Japanese characters.In addition, other symbol sets may be used that would be useful tocommunicate with other animals including mammals besides humans, suchas, primates, dogs, and horses. Each symbol set could be customized toeach animal using the tactile communications device of the presentinvention. Each animal using the tactile communications device wouldneed specific training as to the the meaning of each symbol received.Stored with each symbol will be the digital or analogic equivalent setforth as the message is received by data receiver 40. The data stream isthen conveyed to conversion module 44 over the received data transferbus 52 and the appropriate symbol pattern is then conveyed over memorydata transfer bus 54. Conversion module 44 then compares the digital oranalogic data stream to the digital or analogic equivalent of patternsrepresenting each of the symbols received from pattern memory module 42.

Conversion module 44, using the appropriate pattern for the digital oranalogic data received, sequentially fires a sequence of vibromechanicalstimulators, firing one and then the next individually, until thealphanumeric pattern and/or symbol has been traced over the suitablytactile sensitive area of the wearer. As shown in FIG. 1, conversionmodule 44 uses solenoid electrical connections 48 to energize theplurality of solenoids 46 used in stimulator array 34. An example of asequential firing of these solenoids 46 for tracing the Arabic numeralszero through nine is depicted in FIGS. 8a through k. The particularsequence of sequential firing of vibromechanical stimulators depicted inFIG. 8 is not the only sequence of patterns available to the presentinvention. The present invention anticipates many different firingsequences for creating patterns for any of the alphabet, number orsymbols available to any of the written languages. The present inventionalso anticipates the use of artificial languages and codes that may beused to communicate with the use of the present invention.

As depicted in FIG. 8(a), each element in housing face aperture array 60in housing face 58 has been sequentially numbered from one to eighteen.As used, tactile communication device 30 is inverted over the skin of awearer such that the pattern traced on the skin will be normal to theperson's perception but will be necessarily inverted if one were to lookdirectly at aperture array 60. FIG. 8(b) depicts one of the possiblesequences for generating the number “1” by sequentially firing thevibromechanical stimulators associated with apertures labeled 1, 2, 3, 4and 5. The pattern that is traced begins with firing the vibromechanicalstimulator associated with aperture 1 individually and then sequentiallyfollowed by vibromechanical stimulator at aperture number 2, then at 3,then at 4, and finishing at 5. In FIG. 8(c), the number “2” is traceableusing the following firing sequence of 2, 6, 9, 15, 11, 7, 4, 5, 8, 13,and ending with aperture 18. The number “3” has the firing sequenceshown in FIG. 8(d) of 1, 6, 9, 14, 10, 7, 12, 18, 13, 8 and 5. Thenumbers “5”, “6” and “7” as depicted in FIGS. 8(f), (g) and (h),continue the linear sequential firing of vibromechanical stimulatorsthrough those apertures as shown in each of these three figures.

Numbers such as “4”, “8” and “9” are depicted in FIGS. 8(e), 8(i) and8(j), and involve more complex patterns. For example, the number “4” inFIG. 8(e) uses sequential firing of two linear patterns. The firstsequential firing begins with 1 and continues with 2, 3, 7, 11 and endswith 16. The number “4” pattern is then completed with the secondsequence firing beginning with 9, then 10, 11, 12, and ending with 13.Note that the vibromechanical stimulator associated with aperture 11 isused at two different times during the pattern tracing.

FIG. 8(i) depicts a firing sequence useful for the number “8” beginningwith aperture 16, then going through the sequence 15, 14, 9, 6, 1, 2, 3,7, 11 and returning to 16. Firing 16 a third time, the sequence thencontinues through 17, 18, 13, 8, 5, 4, 3, 7, 11, and finally back to 16.As is seen, the vibromechanical stimulator at aperture 16 has been usedthree times and the three stimulators at apertures 3, 7 and 11 were usedtwice.

The pattern trace for the number “9” as shown in FIG. 8(j) begins ataperture 14 and progresses through apertures 9, 6, 1, 2, 3, 7, 11, 16,15, and then 14 again. 14 then fires again after its slight delay andthe sequence finishes through 15, 16, 17, ending at 18. The number “9”might just as easily have been generated in a linear fashion, forexample by inverting the “6” pattern in FIG. 8(g). The pattern in FIG.8(j) was chosen, as were the patterns for “4” and “8” in FIGS. 8(e) and8(i), because these patterns more closely approximate how these numbersare actually written. Recognition and accuracy have been shown toimprove when construction of the patterns can follow the actual tracingsone might use to create the numbers on paper.

As should be understood, the present invention is not necessarilylimited to such a strict representation. An example of a usefulalternative pattern may be found in FIG. 8(k) where only twovibromechanical stimulators are employed to convey the number zero asdepicted in FIG. 8(k). The number zero is traced by beginning with thevibromechanical stimulator at aperture 5, then jumping to 14 and thenfiring number 5 for a second time. It is understood that the wearer ofthe tactile communication device would necessarily need to know thatthis particular pattern represented the number zero. One obviousalternative is to program a stimulator sequence firing sufficient todraw out a zero.

FIG. 9(a) depicts an example wherein a pilot is tactually receivingspatial orientation information in the form of an artificial horizontactually “played” across array 100. In the example depicted, theairplane's artificial horizon information is conveyed to the controllingportion of array 100 and is used to sequentially fire a series ofvibromechanical stimulators one at time, beginning with a stimulator104, progressing in the direction of the arrow, and ending with astimulator 106. The sequence shown, with the array mounted over thepilots abdomen, would play across the wearer's skin left to right. Allof the stimulators involved in the message have been blackened to moreclearly indicate, pictorially, the message conveyed by the device. Inthis example, the artificial horizon “traced” across the array wouldconvey a message of level upright flight to the pilot.

FIG. 9(b) extends the example of FIG. 9(a) depicting new informationfrom the airplane's artificial horizon tactually “played” across array100. In this example, the horizon information is used to sequentiallyfire a series of vibromechanical stimulators one at a time, beginningwith a stimulator 108, and progressing in the direction of the arrowending with a stimulator 106. The artificial horizon tactuallycommunicated in this example conveys a message of nose-up and rightbank, i.e., an upright climbing right turn.

FIGS. 9(c) and 9(d) taken together depict an example for communicatingnavigational heading information received from a airplane's landingapproach instruments, as well as, an alphanumeric message, a form ofmultiplexing of tactual information receivable from different sourcessent to the wearer of the array. In FIG. 9(c), the airplane's heading inrelation to the runway and glide slope are depicted. The two “lines”tactually drawn sequentially are comprised of horizontal line for theglide slope represented by the sequential firing of vibromechanicalstimulators beginning with a stimulator 112, moving in the direction ofthe arrow and ending with a stimulator 114. The alignment with therunway is represented by the sequential firing of vibromechanicalstimulators beginning with a stimulator 116, moving in the direction ofthe arrow and ending with a stimulator 118. Sequential firing of thestimulators for glide slope from left to right, like the example givenabove, represents upright flight. Sequential firing of the stimulatorsfor runway align from top to bottom could represent descent of theairplane at that moment from information received from the rate ofdescent instrument. Sequential firing from bottom to top could representascent. In the example depicted, the pilot is tactually receivingnavigational information that the airplane is descending on the glideslope and in line with the runway.

Additionally, an alphanumeric message is tactually communicated to thewearer using a corner of large array 100 and represented by thesequential firing of stimulators beginning with a stimulator 120 andending with a stimulator 122. In the given example, the number “six” hasbeen “traced”. Other corners of large array 100 may be usedsimultaneously as additional tactual communicators, tactually conveyinginformation from any number of sources.

FIG. 9(d) depicts glide slope information represented by the sequentialfiring of vibromechanical stimulators beginning with a stimulator 124,moving in the direction of the arrow and ending with a stimulator 126.The alignment with the runway is represented by the sequential firing ofvibromechanical stimulators beginning with a stimulator 128, moving inthe direction of the arrow and ending with a stimulator 130. In theexample depicted, the pilot is tactually receiving navigationalinformation that the airplane is upright, descending, but above theglide slope, and is left of the runway. Another alphanumeric element istactually transmitted in the lower corner of array 100 using the numberfour as the example and represented by the sequential firing ofstimulators beginning with a stimulator 132, progressing sequentially toa stimulator 134, then finishing from a stimulator 136 and ending with astimulator 138, “tracing” a number four.

As noted above, the illusion of linear continuity of the presentinvention wherein letters, numbers and other complex symbols arecognitively recognizable from tactile patterns generated by a twodimensional array of vibromechanical stimulators. This illusion isaccomplished by spacing the vibromechanical stimulators within the twopoint discrimination threshold for the tactile sensitive area to bestimulated and using the vibromechanical stimulators one stimulator at atime in sequence. If two or more stimulators are used simultaneously,the illusion of linear continuity would not be created because the twoor more simultaneously firing vibromechanical stimulators would not beperceived as individual or discrete vibromechanical stimulators but as asingle point. The present invention does not use a scanning technique offiring multiple vibromechanical stimulators to scan a letter, number orcomplex pattern across the tactile sensitive area and therefore spatialresolution of a letter, number or complex symbol is not needed with thepresent invention. A number of vibromechanical stimulators are availableto those skilled in the art and include solenoids, bimorph ceramics andpiezoelectric crystals and ceramics.

Referring to our FIGS. 10 and 11, there are shown various placements forthe vibromechanical stimulators of the present invention. Morespecifically. FIGS. 10(a) and 10(b) illustrate two differentmethodologies for positioning of vibromechanical stimulators on thechest and torso of a wearer. In FIG. 10(a), Housing 38 is held in placeby the use of a chest strap 152. By such positioning to this tactuallysensitive area of the body, the navigation information discussed abovecould be appropriately communicated. Further, multiple actuator housing38 can be spaced apart from one another as shown in FIG. 10(b). In thisconfiguration. the signals can easily cover large areas of the skin.

Similarly, the housing 38 could be positioned in various locations onthe user's head. For example, as shown in FIG. 11(a), housing 38 ispositioned on the forehead through the use of a head strap 150. Thisattachment mechanism is modified slightly in FIG. 11(b) to include anoverhead strap 154, thus positioning housing 38 on an upper portion ofthe forehead. Alternatively, in FIG. 11(c), housing 38 is positioned onthe top of the head again using cross strap 154.

As with the stimulators placed on the chest and torso of a wearer,multiple stimulators could be spaced apart on the head. Three suchexamples are shown in FIGS. 12(a), 12(b) and 12(c), using overhead strap154 and headband 150.

In a number of studies using solenoids as the vibromechanicalstimulators, several variables were determined to be influential increating the illusion of linear continuity and a wearer's ability tocognitively recognize letters, numbers, and complex symbols. Thesevariable parameters were: the total number of vibrations for eachsolenoid used to generate a character, the delay time between a solenoidfiring and the next solenoid to fire, the duty time for the solenoid,and the delay time between the end of creating of one character to thebeginning of the creation of the next character. Appropriate electroniccontrol circuits for generating and delivering electrical pulses tosolenoids were developed and are familiar to those skilled in the art.Components used include a suitable power source, a receiver, a pulsegenerator, a set of patterns programmed within a memory buffer and acontrol circuit for comparing the received message components with thepattern set in memory and generating a sequence of pulses deliverable tothe appropriate sequence of solenoids to tactually convey the pattern ofthe message. Electronic circuits capable of modifying the aboveparameters were chosen.

Studies using a device for conveying arabic numerals were also conductedto determine a useful range of values for the parameter variablesdiscussed above. The range of total number of vibrations per solenoidwas from two to fifteen vibrations with five as the preferred number ofvibrations. The solenoid duty time was tested having two variables andusing a square wave pulse: the actual solenoid on time in millisecondsand the solenoid off time in milliseconds. A useful range for solenoidon time was from two to twenty milliseconds. A useful range for solenoidoff time was from two to ten milliseconds. The preferred solenoid dutytime was fifty percent with a solenoid on time of ten milliseconds and asolenoid off time of ten milliseconds. Therefore the entire solenoidduty cycle time is preferably twenty milliseconds with a range from fourto thirty milliseconds. This equates to a vibration frequency range offrom 33 Hz to 250 Hz with a preferable frequency of 50 Hz.

The character delay setting is that programmable period betweencompletion of the sequence for one letter, number, reference frame orcomplex symbol to the onset of inscribing the next letter, number,reference frame or complex symbol. Studies have shown this range to besubstantially broad with a delay period as short as ten msecs to greaterthan three seconds. There does not appear to be any physical limitationto this delay. Rather, a cognitive perception of a character becomes thefunctional limitation. The subject should be able to discern thecharacter being inscribed at a cognitive level prior to the onset of thenext character to be delivered. The parameter reduces to the functionlevel of the subject to cognitively understand what is being deliveredtactually before receiving the next character. This character delaysetting becomes a functional speed setting for the subject wearer andgenerally determines how fast a message will be delivered to thesubject. This control parameter is therefore subject to individualpreference. The wearer should be able to control the speed with which amessage is delivered.

As discussed above, for FIG. 6, aperture 70 with its associatedvibromechanical stimulator was initially described as an asymmetricallyplaced aperture for anticipated purposes of prompting that a conditionprevious may change. Use of a prompter vibromechanical stimulator wasuseful in studies in order to assist some subjects having difficultywith some letters, numbers or other complex characters. Study revealedthat for some subjects there were a few symbols, only a few in totalnumber, where the subject had difficulty in accurately perceiving thetactually conveyed symbol. When the subject was prompted just prior todelivery of the difficult letter, number or complex character, thesubject was quickly placed on notice that the next character would beone of these few. This type of prompting substantially increased bothspeed of delivery of messages as well as accuracy. As noted above, theuse of a prompter is also ideal for circumstances where the subjectwearer is to be notified that there will be a change in the message. Forinstance, switching from letters to numbers or to complex charactersthat have been encoded with alternative meanings. Additionally,relatively simple changes in state are communicated quickly, such asdistinguishing a.m. from p.m. when receiving a time message.

The foregoing description is considered as illustrative only of theprinciples of the invention, and since numerous modifications andchanges will readily occur to those skilled in the art, it is not adesire to limit the invention to the exact construction and operationshown and described. Accordingly, all suitable modifications andequivalents may be resorted to, falling within the scope of the presentinvention.

I claim:
 1. A tactile communications device, suitable for wearing by atactually sensitive user, for receiving and converting a communicationsdata stream into a tactual message that can be perceived by the user,the device comprising: (a) a housing including a face surface abuttablypositionable over a surface of the user suitably sensitive to tactualstimulation; (b) a tactile stimulator array mountable within the housinghaving a plurality of vibromechanical stimulators positionable adjacentthe face surface, the vibromechanical stimulators having a tactileeffector suitable for impinging the surface of the user when thevibromechanical stimulator is energized; (c) a power source operablyconnected to the tactile stimulator array suitable for powering at leastthe tactile stimulator array; (d) a receiver, operably connected to thepower source, for receiving a communications data stream including atleast navigational and orientation data; and (e) a controller, operablyconnected to the power source, receiver and the tactile stimulatorarray, for independently and sequentially controlling eachvibromechanical stimulator, using one vibromechanical stimulator at atime, to tactually stimulate the surface of the user in at least oneline pattern equivalent to the received navigational and orientationdata stream.
 2. The device of claim 1 in which the housing is attachableto an appendage of the user.
 3. The device of claim 1 in which thehousing is attachable to a surface suitable for gripping by the user. 4.The device of claim 1 in which the housing is abuttably positionableover a suitably tactile sensitive mucus membrane of the user.
 5. Thedevice of claim 1 in which the plurality of vibromechanical stimulatorscomprises a plurality of electromechanical solenoids.
 6. The device ofclaim 1 in which the plurality of vibromechanical stimulators comprisesa plurality of rods of piezoelectric material.
 7. The device of claim 1in which the plurality of vibromechanical stimulators comprises aplurality of rods of bimorphic ceramic material.
 8. The device of claim1 in which the plurality of vibromechanical stimulators comprises atleast 100 vibromechanical stimulators, the receiving means includesmeans for recieving alphanumeric and symbol communications data streamsand the control means includes means for simultaneously controlling atleast two portions of the tactile stimulator array independently so asto convey at least two separate communications data streams.
 9. Thetactile communication device of claim 1 wherein the face surfaceincludes a plurality of apertures disposed in a pattern over the facesurface of the housing, and wherein tactile effector is capable ofprotruding through an associated aperture and impinging the surface ofthe user.
 10. The tactile communication device of claim 1 wherein thehousing further has an internal face surface opposite the face surfaceand wherein the tactile effectors interact with the internal facesurface, causing the face surface to impinge the surface of the user.11. The tactile communications device of claim 1 wherein the linepattern is a substantially straight line.
 12. The tactile communicationsdevice of claim 1 wherein the line pattern is a curved line.
 13. Thetactile communications device of claim 1 wherein the controller causestactile stimulation in a plurality of line patterns equivalent to thereceived navigational and orientation data stream.
 14. The tactilecommunications device of claim 13 wherein the plurality of line patternsincludes a first substantially straight line and a second substantiallystraight line, the first and second substantially straight lines beingsubstantially perpendicular with one another.
 15. The tactilecommunication device of claim 14 wherein the first substantiallystraight line is indicative of navigational attitude information and thesecond substantially straight line is indicative of navigational headinginformation.
 16. A tactile communications method for receiving andconverting communication elements of a data stream into a tactualmessage perceptible to a user, the method comprising the steps of: (a)providing a housing having a substantially flat surface including aplurality of apertures in a substantially two dimensional array; (b)providing an electrical power source; (c) mounting a tactile stimulatorarray, operably connected to the power source, within the attachmenthousing having a plurality of vibromechanical stimulators, positioningeach vibromechanical stimulator adjacent a corresponding aperture; (d)positioning the tactile stimulator array and housing abuttably over asuitably tactile surface area of the user; and (e) providing controlmeans, electrically connected to the electrical power source and thetactile stimulator array, for independently and sequentially controllingeach vibromechanical stimulator, the control means including the stepsof: (e1) receiving a communication data stream including navigationaland orientation data; (e2) converting the received communication datastream into a tactual pattern stream of at least one substantiallystraight line corresponding to the communication data streamnavigational and orientation data; and (e3) turning on and off asequence of vibromechanical stimulators, one vibromechanical stimulatorat a time, according to the tactual pattern stream of at least one line;such that the sequence of vibrating stimulators stimulating the surfacetactually is perceived cognitively by the user as the communicationsmessage.